The theory of detecting the Intra-cavity Laser Absorption Spectroscopy by utilizing a continuous-scan high-resolution Fourier-transform interferometer is introduced.The method to record the position and intensity of absorption lines with the Fourier-transform Intra-cavity Laser Absorption Spectrometer is discussed.By recording the atmospheric water absorption in the region of 12450—12700cm-1,the reliability of this method is investigated.And the technique is applied to record the νOD = 5 stretching overtone of the deuterated water(D2O and HDO).